There is disclosed a method of forming a high luminosity inorganic coating on an aluminium or aluminium alloy article, wherein the article is immersed in an electrolyte and subjected to a plasma anodising process, wherein the coating has a luminosity L*≥80.0% and comprises at least 50 wt % gamma alumina. Also disclosed are inorganic coatings formed by the method, and aluminium or aluminium alloys coated by the method.
−1), formed by plasma electrolytic oxidation on a surface comprising aluminium, magnesium or titanium. There is also disclosed a plasma electrolytic oxidation process for generating dielectric oxide coatings of controlled crystallinity on a surface of a metallic workpiece, wherein at least a series of positive pulses of current are applied to the workpiece in an electrolyte so as to generate plasma discharges, wherein discharge currents are restricted to levels no more than 50 mA, discharge durations are restricted to durations of no more than 100 μs and are shorter than the durations of each the positive pulses, and/or by restricting the power of individual plasma discharges to under 15W. There is also disclosed an insulated metal substrate capable of withstanding exposure to high temperatures (over 300° C.) and thermal shock or repeated thermal cycling of over 300° C., as a result of excellent adhesion of the insulating dielectric to the metal substrate, and the mechanically compliant nature of the coating (E˜20-30 GPa). Furthermore, there is disclosed a method of making these insulated metal substrates so thin as to be mechanically flexible or pliable without detriment to their electrical insulation.
C30B 7/12 - Single-crystal growth from solutions using solvents which are liquid at normal temperature, e.g. aqueous solutions by electrolysis
C30B 7/14 - Single-crystal growth from solutions using solvents which are liquid at normal temperature, e.g. aqueous solutions the crystallising materials being formed by chemical reactions in the solution
C30B 30/02 - Production of single crystals or homogeneous polycrystalline material with defined structure characterised by the action of electric or magnetic fields, wave energy or other specific physical conditions using electric fields, e.g. electrolysis
H05K 7/20 - Modifications to facilitate cooling, ventilating, or heating
G01R 19/00 - Arrangements for measuring currents or voltages or for indicating presence or sign thereof
The present invention relates to a photocatalyst and a method of manufacturing a photocatalyst. More specifically, the present invention relates to a high surface area TiO 2 photocatalyst formed by electrolytic discharge oxidation (EDO) of a substrate comprising titanium. A flexible high surface area photocatalyst architecture comprising a compliant, cohesive, well-adhered and highly porous surface layer of the anatase phase of titanium dioxide is provided. The highly porous surface layer of the anatase phase of titanium dioxide is formed in a single step by the electrolytic oxidation of a titanium surface on a permeable, flexible, and electrically conductive substrate sponge structure.
There is disclosed a method for producing corrosion and erosion-resistant mixed oxide coatings on a metal substrate, as well as a mixed oxide coating itself. A surface of the substrate metal is oxidized and converted into a first coating compound comprising a primary oxide of that metal by a plasma electrolytic oxidation (PEO) process. One or more secondary oxide compounds comprising oxides of secondary elements not present in conventional alloys of the substrate metals at significant (>2 wt %) levels are added to the first oxide coating. The source of the secondary element(s) is at least one of: i) a soluble salt of the secondary element(s) in the electrolyte; ii) an enrichment of the surface of the substrate metal with secondary element(s) prior to PEO processing; and iii) a suspension of the secondary element(s) or oxide(s) of the secondary element(s) applied to the oxide of the metal after this has been formed by the PEO process.
A process for the corrosion protection of metals such as magnesium, aluminium or titanium, where at least two steps are used, including both plasma electrolytic oxidation and chemical passivation. The combination of these two processing steps enhances the corrosion resistance performance of the surface beyond the capability of either of the steps in isolation, providing a more robust protection system. This process may be used as a corrosion protective coating in its own right, or as a protection-enhancing pre-treatment for top-coats such as powder coat or e-coat. When used without an additional top-coat, the treated parts can still retain electrical continuity with and adjoining metal parts. Advantages include reduced cost and higher productivity than traditional plasma-electrolytic oxidation systems, improved corrosion protection, greater coating robustness and electrical continuity.
C25D 11/30 - Anodisation of magnesium or alloys based thereon
C25D 11/26 - Anodisation of refractory metals or alloys based thereon
B05D 3/14 - Pretreatment of surfaces to which liquids or other fluent materials are to be applied; After-treatment of applied coatings, e.g. intermediate treating of an applied coating preparatory to subsequent applications of liquids or other fluent materials by electrical means
An electrical power substrate comprises a metallic body at least one surface of the body having a coating generated by plasma electrolytic oxidation (PEO). The coating includes a dense hard layer adjacent the said surface of the metallic body, and a porous outer layer. Electrically conductive elements are attached to the said coating.